Novel chemical probes to investigate the metabolism and mode of action of insecticides

Systemic agricultural insecticides are potentially exposed to a wide range of detoxification enzymes, both within the crop plant and within the target insect, and thus need to be resistant to the myriad of detoxifying enzymes, if they are to reach the molecular target site in sufficient concentrations to be biologically active. Given the abundance of detoxification systems in plants, pinpointing the specific enzymes responsible for the removal of insecticides can be very challenging. Identifying and understanding the relationship between insecticide degradation and metabolic enzymes should improve our ability to design selective insecticides in the future.

This project will develop a generic approach for the rapid identification and characterisation of the metabolising enzymes responsible for detoxification of specific insecticides. Insecticides will be immobilised and the resulting conjugates will be employed as pull-down probes; proteomic analysis of the interactome protein fractions will ensue. Covalent cross-linking ‘warheads’ will also be generated and attached to the insecticides in order to target the interactome, and will be monitored using fluorescence microscopy in insect cells and/ or plant cell. Overall, the project will involve the integration of synthetic chemistry, chemical biology and biochemistry to create a bespoke solution to identify the key P450 enzymes involved in insecticide metabolism in specific plants and to track their spatio-temporal distribution in cells